1. Technical Field
The present invention relates to a mobile communication device having an alphanumeric keyboard and more specifically a mobile communication device having an alphanumeric keyboard including a keypad having a layout similar to a mobile communication device keypad.
2. Discussion of Related ArtA broad number of different keyboards is known in the art and widely used. Keyboards allow users to input alphanumeric and numeric symbols in a device, such as typewriters and today mostly personal computers and laptops. Therefore, QWERTY keyboards and national variants like the german QWERTZ keyboards have at least three staggered rows of keys primarily assigned to character signs and punctuation marks and a single row of keys arranged above which is assigned to numeric signs. An extended keyboard version includes an additional calculator style keypad assigned to numeric and mathematical signs.
The number of device applications and device functions provided by mobile communication devices to the users increase rapidly with each generation. The increasing number of device applications and device functions result from the increasing capabilities of the hardware implemented in the mobile communication devices and the demands of the user. Of course, an increasing number of device applications and device functions result in parallel in a more complex and more sophisticated handling of the total mobile communication device.
An appropriate design of the mobile communication device is a great challenge to the mobile communication device manufacturer, since partial contradictory requirements have to be fulfilled. On the one hand, the device applications and device functions should be accessed quickly and in an easily understandable fashion. On the other hand, the number of input means, especially the number of keys, is limited in order to realize a mobile communication device design of small size and low weight as well as not to confuse users due to a too high number of keys.
The double and triple assignment of keys of the keyboard to reduce the total number of keys and to minimize the total size of the keyboard is also well known. Further, especially handheld communication devices are known which have QWERTY like keyboards with integrated keypads corresponding to the conventional telephone style ITU-T keypads provided in conventional mobile phones for entering telephone numbers. Such an ITU-T keypad comprises the numbers 0 to 9 and the symbols “*” and “#” in a pre-determined standardized configuration.